6 Microbes Saving the Environment

By | February 25, 2020


Thanks to Brilliant for supporting this episode
of SciShow. Go to Brilliant.org/SciShow to learn how you
can take your STEM skills to the next level! [♪ INTRO] Ever since humans found out germs were a thing, we’ve had a vendetta against microbes. The idea that death can be doled out by stuff
we can’t even see is pretty unsettling. So we invented antibacterial soap and antibiotics
and antifungals, and we went a little bit overboard in the
end with the anti-everythings. And as a result, we’ve often ignored the
existence of good microbes. With the exception of the ones that give us
cheese and yogurt and beer and bread, of course. We’ve always given them a free pass. But good microbes do a lot more than make
yogurt yogurty and cheese cheesy. They also help us digest food and fight illness. And the more we’ve learned about them, the
more we’ve realized that they have the capacity to do really big
things. Like help us protect endangered species and
maybe even undo some of the big mistakes we have made as humans. So here are six examples of microbes helping
to save the world. The first, koalas. They are notoriously picky
eaters. Although they’ve occasionally been seen
eating leaves from other trees, for the most part, they
eat eucalyptus leaves. And that’s pretty much it. And they’re even picky about which species
of eucalyptus they eat. So, these things are cute, but they’re also,
like, the worst dinner guests of all time. Thankfully, that’s not too much of an issue
for them. Australia is full of eucalyptus trees, and
there isn’t a lot of competition for it since the plant’s leaves are toxic. Koalas can only digest it thanks to a special
type of gut bacteria — one they acquire as babies when they eat what’s
called pap. That’s a special kind of microbe-rich poop that they get from their moms. So overall, this lifestyle works for them.
Or it did. In the next sixty years, climate change is
expected to reduce the distribution of most Australian
eucalyptus species by more than half. Urbanization and habitat destruction are also
a threat, and that was before the devastating Australian
wildfires (which started in 2019) added even more pressure. In response to this, you would think koalas
might switch to another food source. But they don’t always do that — in part,
because their digestive systems are just so specialized to one or a few species of eucalyptus. Fortunately, there’s a pap for that. In 2019, scientists successfully transplanted
the gut bacteria from koalas who ate one type of eucalyptus,
called messmate, into the guts of those who were used to eating
another type, called manna gum. Specifically, they gave the manna gum koalas
capsules that contained microbes extracted from the
poop of messmate koalas. Which is like, you know, slightly less gross
than eating actual poop. The scientists hoped that the unique microbes
from the messmate koalas would help the other group’s bodies digest
the new food. And at the end of the experiment, the manna
gum eaters were eating more messmate. So… success! To be fair, though, the researchers weren’t
totally sure if this happened because of the increase in
gut bacteria, or if the gut bacteria were increasing because
the koalas were eating more messmate for some other reason. So there’s room here for more research. But it’s intriguing to think that poop and
the bacteria it contains might one day help save a species. To the delight of poop joke enthusiasts everywhere. Next, malaria is one of humanity’s most
deadly foes. But we aren’t the only species that gets
it. Bats, reptiles, birds — there are a lot
of animals on malaria’s hit list, although not all of them are affected by it
the way we are. Take avian malaria, for example. Although it can shorten birds’ lives, it
usually doesn’t kill them. In some isolated places, though, avian malaria
can be deadly. Like in Hawai’i. Until humans came along, birds in Hawai’i
had no exposure to the malaria parasite — because there
were no mosquitos on the Hawaiian Islands. According to a local legend, that only happened
when a bunch of sailors dumped a barrel full of water and mosquito
larvae into the wetlands around Lahaina. Which… did that seem like a good idea? When the mosquitos arrived, so did the avian
malaria parasite. And after native Hawaiian birds were introduced
to it, ten species went extinct. Thankfully, there might be a way to control
this disease in Hawai’i and all over the world. And it’s not insecticide — because although
that’s been the standard for years, mosquitos have an annoying habit of becoming
resistant to it. Instead, scientists are testing a new weapon:
a bacteria called Wolbachia, which naturally infects a lot of other insects, but not malaria-carrying mosquitos. But in a 2009 experiment, scientists took some
Wolbachia and managed to infect a group of Aedes aegypti
mosquitoes with it. Those are mosquitos that carry a whole bunch
of diseases, including avian malaria. Then, they had those mosquitos drink the blood
of chickens infected with the avian malaria parasite. And normally, this would result in the insects
becoming malaria carriers. But in this case, the mosquitos actually appeared
to have a stronger immune response, and fewer malaria
parasites developed. Right now, scientists aren’t completely
sure why this works, but it could be because the mosquito’s immune
system gets a boost in the presence of Wolbachia. And as a bonus, this method also works to
prevent other diseases, including mosquito-borne human ones like dengue
and Zika, which are also carried by A. aegypti. If you’ve ever tried to enjoy a day at one
of the Midwest’s Great Lakes, you may have noticed a bunch of tiny, pokey
shells all over the beach. Those are invasive zebra mussels, and they’re
there just to ruin your afternoon. Or so it seems like, anyway. In reality, invasive mussels are a huge problem not just because it hurts to step on them, but because they are extremely difficult to
control. Juveniles are microscopic and will attach
themselves to almost any hard surface, which means boat owners can accidentally transport
them from one lake to another. And when they do, these mussels clog the intake
pipes that feed city water supplies, they hog nutrients,
and they steal food from native fish and other aquatic species. In the US, they cost the economy around a
billion dollars every year. Fortunately, scientists have figured out how
to use the mussels’ own diet against them. See, mussels usually eat plankton, but they also eat bacteria. And after testing more than 700 strains, researchers
learned that a common, usually harmless bacteria called P. fluorescens
produces a toxin that’s dangerous to the mussel’s digestive
system. It causes cells to rupture and die in the
mussels’ digestive gland, and that ultimately kills the animal. Maybe more importantly, though, when mussels
feed on this bacteria, they don’t notice anything’s wrong; they
seem to think they’re having just a nice and lovely day. And they will keep eating until they die. This is huge, because although chemicals like
chlorine are a more obvious threat to the animals,
mussels can sense those chemicals and will shut their valves
to protect themselves. The bacteria, meanwhile, just masquerades
as normal food. Scientists have been looking into this biological
solution to the invasive mussel crisis for decades,
but in the last few years, that research has finally started translating
into practical use. So someday, we might be thanking P. fluorescens
for our clean, mussel-free beaches. A common forest salamander has a weird way
of weaving in and out of its clutch of eggs. And it’s not just being mysterious: It’s
transferring an antifungal bacteria from its skin onto its eggs. The bacteria helps protect the eggs from a
common type of fungus. But when scientists saw this, they wondered
if there might be another application for that antifungal. They wanted to know if it could also be used
to prevent a deadly chytrid fungus, which infects more than 500
amphibian species around the world. Biologists have tried a number of strategies
to control this fungus, but none of them seem practical for large
populations, and others have had nasty side effects. So hey, maybe this salamander stuff could
be the solution. In 2009, researchers tested their hypothesis
on mountain yellow-legged frogs, which are very susceptible to chytrid. It attacks tadpoles’ mouths and damages
adults’ skin, so infected frogs typically die. In their experiment, scientists bathed frogs
in a bacterial soup made from J. lividum, the same bacteria found
on the skin of those salamanders. And when those frogs were exposed to the fungus,
none of them died. Meanwhile, frogs who didn’t get a bacterial
bath weren’t so lucky. Over 80 percent of them didn’t survive the
fungus. This treatment seems to work because the
bacteria produces an antifungal called metabolite violacein, which inhibits
the fungus somehow. Scientists have tried to figure out how this
works, but they’re not sure. They think it might be a byproduct of violacein’s
interactions with other bacteria. In any case, it works, so they’re going
to keep doing it — and not just for the amphibians. Because violacein also has antibacterial and
even anti-cancer properties. So it might be able to protect us, too. You might not see it when you look at them,
but coral really need algae. The coral provides the algae with a safe place
to live, and the algae give the coral all kinds of
nutrients it needs to survive. So when that relationship is disrupted, bad
things happen. Like coral bleaching. In the presence of stressors like rising temperature, corals expel their algae, which makes the
coral turn white and become vulnerable to disease. Bleaching can also stunt their growth and negatively affect their ability to reproduce. And a severe bleaching event can kill them. When we filmed this in early 2020, 27% of
the world’s coral reefs had already been lost due to bleaching, and experts think that number is likely to
go up. But maybe it doesn’t have to. In 2018, researchers created a cocktail of
different microorganisms, each of which possessed certain protective
qualities. Some were chosen for their ability to produce
catalase, which can reduce the concentration of dangerous, reactive oxygen species — ones that would
damage proteins or genetic material and kill cells. Other microbes were good at converting nitrogen into a nutrient the corals could use, while
others were aggressive toward pathogens. And when scientists added these microbes to
a coral community, they reduced bleaching in the presence of
warmer water and pathogens! Which is great! That doesn’t mean the microbes prevented
or reversed bleaching, though — they were just able to help the coral
survive the bleaching event with fewer ill effects. It still takes a reduction in water temperature
and the return of algae to get the coral back on track. But maybe something like this could keep corals
afloat during short warm spells. Finally, cleaning the messes humans have made
remains one of our biggest challenges. And nowhere is this more evident than in superfund
sites. These are some of the most polluted places
in the United States, and they get their name, superfund, from the
trust Congress established to help pay for their cleanup. Not superfun (it’s hard to say it), superfund. And that cleanup is expensive and it’s dangerous
— for humans and for our non-human helpers. Poplar trees, for example, can naturally help
remove a common industrial solvent called trichloroethylene,
or TCE, from heavily-contaminated sites. But in the process, the toxicity may cause
them to become stunted: Their leaves can turn yellow, and their branches
can wither. Some may even die. So, there’s a balance here. Because trees are a great way to clean up
polluted areas… but we also don’t want to kill them. Cue the microbes! In 2017, researchers discovered that poplar
trees fortified with a kind of Enterobacter bacteria were
able to remove the TCE with fewer ill effects. This specific strain of Enterobacter — called
PDN3 — breaks down the TCE and releases a harmless chloride ion instead. Researchers inoculated poplar trees by exposing
their roots to the bacteria for one week, then checking to make sure that
the bacteria was able to colonize the roots. The trees that were inoculated not only removed
more TCE from the environment, but they were also healthier and larger than
the trees that didn’t get any microbial assistance. Because, like, when a toxin isn’t trying
to wither your leaves and kill you, it turns out you can do your job better. So, despite our aversion to them, because
yes, they can kill you, almost all microbes are either benign or positive. They make your yogurt yogurty and they make
your cheese cheesy. But more than that, they can also help or even save species across the planet. If you want to learn more about microbes,
good news: There is so much to learn about them, from
their behavior to their genetics. But if you really want to dive in, it might
be good to know a bit about computational biology. This field combines elements of physics, computer
science, and bio. And if you want to get a sense of what it
looks like, you can check out Brilliant’s Computational Biology course. It covers things like genomes, DNA composition,
and molecular folding — all things that are important in the lives
of microbes. And like all of Brilliant’s courses, it
does that in a really engaging, easy-to-understand way. So, props to them! If you want to check it out, you can go to
Brilliant.org/SciShow. And the first 200 people to sign up there
will get 20% off the annual Premium subscription. [♪ OUTRO]

100 thoughts on “6 Microbes Saving the Environment

  1. Trevor Jones Post author

    4:02 hold up, you mean to tell me there was a place other than Antarctica where mosquitoes didn’t live and people willingly brought them there? Wtf humanity?

    Reply
  2. PeachesCourage Post author

    Like this one thanks Flint Michigan could use this too

    Reply
  3. pogan1983 Post author

    I switched off the sound and… I thought you are …in a deep need. Do you, you all, become instructed to wave hands like mad? Nevertheless, thank you for another film, I like watching you.

    Reply
  4. 47 Steez Post author

    Hey scishow I have a class and we were talking about blood types and I was wondering how did blood types evolve and why do we have them?

    Reply
  5. Lorax Dave Walters Post author

    I heard about a biohacker slinging poop pills… JK unless you are rich enough to afford your own medical team, paying for illegal healthcare is a bad idea. If you are forced to live outside the economic system of credit and top quality health insurance, it might be your only choice.
    OK good times.

    Reply
  6. FrostWatch Post author

    I already knew about the koala poop thing. From anime of course.

    Reply
  7. PamdaDev Post author

    *Cientist runs into the room

    – We did it, we finally did it. We found a solution, we can save your species.

    *everyone sighs and cries in relief and joy

    – here, eat this other creature's poop



    ..

    .

    Reply
  8. LilKidAttacker Post author

    I know it’s not living but… corona virus will end up cutting down a lot of potential emission and pollution…

    Reply
  9. Pingonaut. Thomas C. Post author

    We don’t need bacteria to save birds from Malaria in Hawaii. We have the ability to KILL ALL MOSQUITOS with genetics!

    Reply
  10. C S Post author

    Zebra muscles are from Russia….we oughta know by now the damage invasive species can do. There are native species they out compete.
    https://www.voicenews.com/news/written-off-as-doomed-native-mussels-survive-zebra-mussel-invasion/article_c44cd58d-e019-5492-92ea-0a39b96b6bb9.html

    Reply
  11. scrunglenüt Post author

    wouldn't a disease that shortens a lifespan technically be deadly? LOL

    Reply
  12. nab 6215 Post author

    #Superfund Where is NJ? Whenever Republicans are in office environmental remediation companies live on commercial contracts. Been there. Done that.

    Reply
  13. Leah McGrew Post author

    OMG – I love your giraffe shirt…. Oh, it was an interesting talk too.

    Reply
  14. _B -Lowe_ Post author

    Did anybody watch that episode on South Park?

    About the poop transplants..

    Reply
  15. LizardVideoDude Post author

    Do mosquitoes actually serve any good purpose? Seems like the entire planet would be better off if mosquitoes were completely exterminated.

    Reply
  16. Jeemon Jose Post author

    Yeah, everyone knows killing invasive mussels is saving the environment, and not fighting it

    Reply
  17. Kelvin Elrick Post author

    "Help keep corals afloat"… they are attached to the ground.

    Reply
  18. Jane Lane Post author

    mussels do help clean up too. they were probably spread by people who wanted to clean up polluted water.
    we had a lot of them in the bay one year, the murky water became clear.

    Reply
  19. Hugh Askew Post author

    The you blame the 'devastating Australian wildfires that started in 2019' on climate change, what gets the blame for the devastating Australian wildfires that have occurred repeated over the centuries when CO2 concentrations were much lower?

    Reply
  20. Diamond Jub Post author

    Microbes: "Well maybe I don't wanna be the bad guy anymore"

    Reply
  21. Chris Flad Post author

    Western NY has 2 great lakes and we are NOT the midwest…. They are just as much ours.

    Reply
  22. Antonio Santini Post author

    Scientists are actual gods at this point, they can manipulate any factor in any scenario and get a result they want. They can just change the laws of nature at will its incredible. They have 0 limiting factors other than imagination and sadly, funds

    Reply
  23. - Post author

    Fosters is Australian for beer and Messmate is Australian for coffee-whitener.

    Reply
  24. Silas Cochran Post author

    This is all wonderful and stuff. But if anybody remembers this is how we got in trouble in the first place. By tampering with nature It is already too late. To fix the balance no pun intended. We are in a world of s***. And we're leaving it. To our children

    Reply
  25. Adam wiggins Post author

    Phage therapy… studied in Russia since we discovered penicillin… great alternative to it

    Reply
  26. Chris Heichel Post author

    So fecal transplants for koalas kind of gross but very cool that they're saving them

    Reply
  27. Prowler Cam Post author

    Have you forgotten that fecal transplants are being done with humans?

    Reply
  28. jaybestemployee Post author

    Koala mother feeds pap(special poop) to baby koala so baby can eat what mother eats
    Human mother frustrated at kid not eating what mother normally eat.
    Seems nature has once again given us the answer.

    Reply
  29. roy romano Post author

    I’ve always been fascinated by the transferring of gut bacteria. Just imagine, people getting cross pollinated with kuala gut bacteria. Then they’d be able to eat eucalyptus leaves without dying. I mean, the ability to just turn anything into food just seems like it has far more implications. Than anything else named in the vid.

    Reply
  30. Ayan Booyens Post author

    I have a friend who’s chemical engineering dissertation was on microbes that could digest rubber because recycling car tires is kind of near impossible. She’s very risk averse so I remember that at some point someone from a Chinese university wasn’t sure how to get a sample of “bugs” through customs so they posted her a book with a like sample bag bookmark. She must’ve thought it was anthrax because she autoclave’d the whole package! I think the mechanical engineers would have just yolo’d with it but maybe there’s a reason that we didn’t get an autoclave (the undergrads are savages who would probably try to make extremely grilled cheese or something)

    Reply
  31. matanuska high Post author

    Using the microbes to kill muscles will it also kill the baitfish that and it’s food that feed on the plankton?

    Reply
  32. KeshmarOrange Post author

    These videos constantly remind me how much I hate the word "gut".

    Reply
  33. Evi1M4chine Post author

    13:10 Why didn’t you say ”Journey to the Microcosmos“??

    Reply
  34. Sergii Zaika Post author

    Pseudomonas fluorescent, not P. fluorescent. P is mathematical abbreviation and =3,14.

    Reply
  35. Sergii Zaika Post author

    Janthinobacterium lividum, men, You searching true bacterial names or not?

    Reply
  36. himssendol Post author

    Old Hawaii was paradise. 🏝
    A tropical island that didn’t have mosquitos!

    Reply
  37. sdfkjgh Post author

    8:01 Dammit, I tried to find that illustration from bogleech about Kermit's last days, but it seems to've disappeared from the web.

    Reply
  38. Quantum Droid Post author

    so if we feed the coala baby with a diffrent milk that mean the baby will able to eat other than leaves?

    Reply
  39. Kittsuera Post author

    so… instead of getting rid of mosquito we should be finding cures for them and getting them on health care programs to reduce the health risks they pose.

    Reply
  40. Andrew Blucher Post author

    They don't know why it works, but they'll keep doing it.

    Bad idea.

    Reply
  41. EliteLemon 171 Post author

    Just a non related question: is not sleeping for 17 hours considered clinically imsane? I read that somewhere. If its true then im insane -_-

    Reply
  42. Helena Schulin Post author

    Pap means cardboard in Danish and it makes koalas even more ridiculous to me.. I love them though…

    Reply
  43. Aurgelmir87 Post author

    Infecting mosquitos with wolbachia sounds like potentially disasterous. I mean wolbachia in other species is associated with the ability of the host to reproduce asexually via parthenogenesis and an increase in the percentage of the species made up of females (which is the sex that bite people and animals). So we could see a mosquito that is cabable of reestablish itself faster after droughts and insecticide campaigns, with a higher percentage of of the bity kind, and if we are really unlucky wolbachia might help them resist other bacterial and viral pathogens that is currently killing off mosquitos.

    Reply
  44. Skylancer727 Post author

    11:25 okay noted, New Jersey is the most polluted place in the country. Not like I needed to be told that.

    Reply
  45. Philip Lindley Post author

    Just human beings pissing in the wind. We should stop trying to interfere in a system so complex we can't possibly see the ultimate effects.

    Reply
  46. Katy Leanne Post author

    Wow he didn’t plug his channel Journey to the Microcosmos that’s about microbes in this video.
    What a humble guy.

    Reply
  47. NovaRyu Post author

    We are the microbes of earth… so we need to get our act right an find a way to be beneficial to our host or we'll be eradicated

    Reply
  48. Mi 28 Post author

    Coalas are just too stupid to survive. They have less intelligence than cockroaches. Like, if you gave it picked eucalyptus leaves it wouldn't know what to do with them, they have to be on a branch.

    Reply
  49. As Cra Post author

    Introducing a microbe into the wild that will wipe out an entire species. I understand that it's an invasive species but stuff like this has been tried many times in the past and always ends in disaster.

    Reply
  50. Layow Post author

    This channel and its sister channels are THE best. And microcosmos is truely a blessing!

    Reply
  51. Shanine Jackman1998 Post author

    Oh those poor coral 😱😭 & those other poor animals!!

    Reply
  52. Pașca Alexandru Post author

    They make your yogurt yogurty, you cheese cheesy and your life life lively.

    Reply
  53. Abu 'Afak Post author

    Cottontail rabbits' babies (here in the USA) are also corprophagous (they eat their mother's poop). They wouldn't be able to digest "grass" as their parents do, if they didn't do this to introduce their guts to the cellicose digesting bacteria their parents carry.

    Reply
  54. Rikki E Post author

    Would be cool if scishow did a video on how plant propagation actually works. As well as plant cloning. It's always been a slight fascination on how my teddy bear vine cuttings will reroot and start to grow another vine. I got the plant about 12 years ago and it's still going strong.

    Reply
  55. Brian Williams Post author

    I wonder if the zebra mussels are part of the reason the Great lakes cleaned up. They are filter cleaners?

    Reply
  56. J B Post author

    Good News! Your aunt Euphemia died and left you her collection of rare Microbes.

    Reply
  57. Charles Markgraf Post author

    3:15 there's room here for more research….shows picture of SLEEPING koala…lol

    Reply
  58. Seanna Baine Post author

    You could stop pushing the myth of climate change, and people would enjoy your videos more.

    Reply
  59. Darin Roodman Post author

    Something you guys might be interested in waxing poetically: https://www.livescience.com/first-non-breathing-animal.html?utm_source=notification

    Reply
  60. Gabriel Martins Post author

    Poplar is a great wood for guitars as well. Poplar burl is gorgeous.

    Reply
  61. Pretty Prudent Post author

    It’s too bad viruses aren’t on our side, because they’re certainly Stronger and more resilient than worthless bacteria when it comes to human health

    Reply
  62. The Real Flenuan Post author

    Muscle-free beaches, you say? Not if Muscle Hank has anything to do about it!

    Reply
  63. meoka2368 Post author

    When one of the tress removes TCE from the ground, what happens to the TCE? Does it get converted into something harmless, or does it re-enter the soil when the tree eventually dies (or air if it is burned)?

    Reply
  64. Chelsea Older Post author

    I don't know of you're aware, but those zebra mussels were purposefully introduced, at least into Lake Erie, to combat the huge blooms of blue-green algae.

    Reply
  65. Jonathan Rhodes Post author

    "Oh, so this is gonna be about practical biological warfare."
    "This bacteria actually strengthens the mosquitoes immune system!"
    "Ah, so it'll be about helpful bacteria, gotcha."
    "Also, this makes mussels explode from the inside!"

    Reply

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